(STRATEGY
    INNERMOST)

(VAR
    X Y Z)
(DATATYPES
    A = µX.< 0, nil, s(X), cons(X, X) >)
(SIGNATURES
    fst :: [A x A] -> A
    from :: [A] -> A
    add :: [A x A] -> A
    len :: [A] -> A)
(RULES
    fst(0(),Z) -> nil()
    fst(s(X),cons(Y,Z)) -> cons(Y
                               ,fst(X,Z))
    from(X) -> cons(X,from(s(X)))
    add(0(),X) -> X
    add(s(X),Y) -> s(add(X,Y))
    len(nil()) -> 0()
    len(cons(X,Z)) -> s(len(Z)))